Volumetric Properties, Compressibilities and Volume Fluctuations in Phospholipid-Cholesterol Bilayers

We conducted detailed measurements of the apparent specific volume of dipalmitoylphosphatidylcholine (DPPC)–cholesterol mixtures in excess water as a function of pressure up to 70MPa (700bar) at 20, 38 and 50°C. The volumetric properties and the isothermal compressibility κ T of the lipid vesicles were determined at cholesterol concentrations, χchol, ranging up to 50 mol. The thermodynamic data are compared with other physico-chemical properties of phospholipid–cholesterol mixtures. Furthermore, the thermodynamic properties of the system are discussed in the light of the various T, χchol–phase diagrams and computer simulation studies published in the literature.

The impact of ”laying on of hands” on well being in patients with advanced cancer

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Background: To determine whether the impact of “laying on of hands” on well being of patients with advanced cancer is more efficient when performed by a person with “healing powers” as compared to an actor. Methods: A total of 80 patients was registered to participate in a randomized, single-blind phase III trial to evaluate the difference in efficacy of “laying on of hands” by either a “healer” or a sham person (actor). Both arms were designed to consist of a total of 40 patients, divided into 5 groups including 8 patients each. Each patient should receive treatment for 5 minutes, 3 times a week. A “Well-being scale” was used to measure differences in treatment outcomes. The primary and secondary endpoint evaluated the difference in the total sum score of the “Well-being scale” between the two arms on day 10 or day 5, respectively. Results: The first run was unblinded by the “healer”. Hence, only the second run was available for comparison. There was no significant difference in sum-score values between the “healer” and the actor (p = 0.34) with regard to the primary endpoint or the secondary endpoint (p = 0.94). After the second run, the “healer” quit and a major protocol violation occurred. Despite this major obstacle, the study was completed by the actor as a descriptive, explorative study. There was a significant decrease in total sum score values after each single treatment (day 1, 3 and 5, p < 0.0001, respectively) for all patients. In addition, a significant improvement in symptoms could be found on day 5 (p < 0.001) after treatment and day 10 (p = 0.0002) as compared to day 1 before treatment. Conclusions: “Laying on of hands” resulted in a significant improvement of cancer or cancer-therapy associated symptoms. The magnitude of improvement obtained was similar when “treatment” was provided by a self declared “healer” or an actor, although the comparison was hampered by protocol vialotions by the “healer”.

No significant financial relationships to disclose.

[What questions are appropriate for predicting the risk of chronic disease in patients suffering from acute low back pain?]

AIM

The objective of the study was to develop a brief questionnaire to determine the risk of chronification for patients suffering from lumbar (low) back pain who are consulting a physician for the first or second time.

METHOD

At the outset, and again after six months, a questionnaire with 167 valid items for chronification was distributed to patients in orthopedic offices. After six months, patients were contacted by mail to inquire whether they were still suffering from back pain. Based on outcome (persistence of back pain/absence of back pain) and by means of logistic regression analysis, those variables were determined that could predict actual chronification.

RESULTS

The following items were predictive: "How strong was your back pain during the last week when it was most tolerable?" and "How much residual pain would you be willing to tolerate while still considering the therapy successful?" (Acceptance value, beta = 0.61), patient's educational level (beta = - 0.44), massage is experienced as bringing relief (beta = 0.44), 5 items of the Zung scale for depression (beta = 0.42), items of the scale for catastrophizing thoughts (beta = 0.41) and items of the scale for feelings of helplessness (beta = - 0.39) of the Kiel pain inventory; duration of the back pain for longer than 1 week (beta = 0.38), pain in other parts of the body (beta = 0.37); and female gender (beta = 0.25)

CONCLUSION

Based on these questions, it was possible to predict the chronification of back pain with a probability of 78.05 %. A corresponding questionnaire and an evaluative table were developed.

[Primary headache in childhood and adolescence. The association between changes in family interaction patterns and therapy success--a pilot study]

INTRODUCTION

Family interaction patterns are often involved in diseases and disorders in childhood and adolescence in complex ways (e.g in their development, maintenance and cure). The present study deals with the role of family factors in success in a pediatric headache therapy consisting of group hypnotherapy and systemic family consultation.

METHODS

A sample of 12 outpatients, aged 9-15 years and balanced in sex, is investigated. Patients were diagnosed by IHS-criteria. Global symptom strain was measured by numeric rating scale (NRS) at pre-appointment and at 9-months follow-up appointment. Also family interaction patterns associated with the occurrence of headache symptoms were measured by content analysis.

RESULTS

We found an association between changes in two independently assessed variables: global symptom strain and family interaction patterns. (1) When patients assessed global symptom strain as unchanged, family interaction patterns associated with headache were also assessed as unchanged by observers; (2) when patients assessed their global symptom strain as positively changed, family interaction pattern associated with headache were also assessed as positively changed by observers.

CONCLUSION

These data provide empirical evidence about when to include family in treatment of pediatric headache: when rigid family interaction patterns associated with headache complicate a symptom change.

Volume, expansivity and isothermal compressibility changes associated with temperature and pressure unfolding of Staphylococcal nuclease

We have characterized the temperature- and pressure-induced unfolding of staphylococcal nuclease (Snase) using high precision densitometric measurements. The changes in the apparent specific volume, expansion coefficient and isothermal compressibility were determined by these measurements. To our knowledge, these are the first measurements of the volume and isothermal compressibility changes of a protein undergoing pressure-induced unfolding. In order to aid in interpreting the temperature and pressure dependence of the apparent specific volume of Snase, we have also carried out differential scanning calorimetry under the solution conditions which are used for the volumetric studies. We have seen that large compensating volume and compressibility effects accompany the temperature and pressure-induced protein unfolding. Measurements of the apparent specific volume and thermal expansion coefficient of Snase at ambient pressure indicate the formation of a pre-transitional, molten globule type of intermediate structure about 10 degrees C below the actual unfolding temperature of the protein. Compared to the folded state, the apparent specific volume of the unfolded protein is about 0.3-0.5 % smaller. In addition, we investigated the pressure dependence of the apparent specific volume of Snase at a number of different temperatures. At 45 degrees C we calculate a decrease in apparent specific volume due to pressure-induced unfolding of -3.3 10(-3) cm(3) g(-1) or -55 cm(3) mol(-1). The threefold increase in compressibility between 40 and 70 MPa reflects a transition to a partially unfolded state, which is consistent with our results obtained for the radius of gyration of the pressure-denatured state of Snase. At the lower temperature of 35 degrees C, a significant increase in compressibility around 30 MPa is indicative of the formation of a pressure-induced molten globule-like intermediate. Changes in the apparent volume, expansion coefficient and isothermal compressibility are discussed in terms of instrinsic, hydrational and thermal contributions accompanying the unfolding transition.

Predicting subjective disability in chronic pain patients

Subjective disability is considered as the variable that reflects the impact of chronic pain on a patient's life. This study examines the questions of which syndrome or patient characteristics determine subjective disability and whether there are differences between samples of patients with chronic headaches and low back pain. Direct pain variables and depression, pain coping strategies, and pain-related self-statements (including catastrophizing) are introduced into multivariate regression analyses as potential predictors of disability using a sample of 151 pain patients. Disability is not predicted by pain severity in patients with headaches or back pain. Psychological variables, especially coping strategies, are far more influential. Coping explains more variance in disability in the headache sample than in the chronic law hack pain group, whereas depression is more relevant for the degree of disability in the back pain sample. In this study, we present a critical analysis of possible interpretations of our results. We point to an overlap of concepts underlying some of the variables used: this overlap also considerably invalidates conclusions drawn from a multitude of studies done in this field, including the one presented. We strongly argue for a conceptual clarification, and consequently for the revision of assessment instruments, before further empirical work in this area is done.

[Pain therapy-integration of psychological diagnosis and therapy.]

A multidisciplinary approach, acknowledged as being the best treatment strategy for a wide range of chronic pain patients, requires cooperation at least between trained professionals in the medical and the psychological disciplines. Psychological criteria are formulated to bridge persisting gaps in the interdisciplinary implementation of pain treatment strategies.